These studies plan to investigate the relevance of conditioning, of the evolutionary concept of "preparednes," and of non-verbal communication to neurosis. They hypothesize that compared to normals, neurotic individuals will show impaired extinction or even paradoxical enhancement of certain types of conditioned responses. Patient volunteers satisfying DSM-III criteria for selected anxiety disorders will be contrasted with matched controls in three electrodermal conditioning paradigms: Differential conditioning, Overshadowing, and Summation. CS exemplars will fall into two categories: presumably "prepared" (pictures of angry human facial expressions) and presumably neutral (pictures of neutral human expressions). The UCS will be a brief pulse of electric shock whose level will be set by the subject in advance to be uncomfortable but not painful. The CR will be measured by the primary dependent variable of skin conductance. Electromyographic (EMG) activities of three selected facial muscles will serve as secondary dependent variables. The studies' designs will be between-subjects with repeated measures. The between-subjects factors will be diagnostic category (neurotic vs. control) and stimulus condition (prepared vs. neutral CS). Analysis of the results will focus on the extinction periods. Phasic changes in skin conductance will be calculated for each extinction trial and subjected to univariate ANOVA for repeated measures. Trend analyses will be performed to detect the presence of paradoxical enhancement of the CR. The EMG data will be analyzed in a parallel manner utilizing multivariante techniques.